You can order Perl books from O'Reilly & Associates, 1-800-998-9938.
Local/overseas is +1 707 829 0515. If you can locate an O'Reilly order
form, you can also fax to +1 707 829 0104. If you're web-connected, you can
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for an online order form.

Programming Perl, Second Edition is a reference work that covers nearly all of Perl, while Learning Perl, Second Edition is a tutorial that covers the most frequently used subset of the language.
You might also check out the very handy, inexpensive, and compact
Perl 5 Desktop Reference, especially when the thought of lugging the 676-page Camel around doesn't
make much sense. Mastering
Regular Expressions, by Jeffrey Friedl, is a reference work that covers the art and
implementation of regular expressions in various languages including Perl.